The invention relates to improvements in so-called hinged-lid packets for arrays of rod-shaped articles of the tobacco processing industry. More particularly, the invention relates to improvements in methods of and in apparatus for making the lids of such packets. Still more particularly, the invention relates to improvements in methods of and in apparatus for making hinged-lid packets of the type wherein the front panel of the lid is reinforced by an elongated strip which overlies the inner side of and, prior to conversion of a blank into a hinged-lid packet, is longer than the front panel.
Blanks for conversion into hinged-lid packets for arrays of parallel cigarettes or other rod-shaped smokers' products are normally made of lightweight cardboard. Such blanks are provided with fold lines so that they can be readily and accurately (predictably) draped around parallelepiped (block-shaped) contents normally consisting of arrays of say twenty parallel plain or filter cigarettes in an envelope of tinfoil or other suitable wrapping material. The lid of a finished hinged-lid packet is pivotable relative to the rear wall of the main portion of the packet so-that it can afford access to or can repeatedly confine the contents of the packet. The front panel of the lid is normally reinforced by a longitudinally extending strip which overlies the inner side of the front panel adjacent the free edge of the latter. Such free edge is adjacent the front wall of the major portion of the packet when the lid assumes its closed or confining position.
The reinforcing strip can be bonded to the inner side of the front panel of the lid, or it can be mechanically clamped or wedged between the lateral panels of the lid. In the latter case, that (first) part of a blank which is to constitute the reinforcing strip in a converted blank (i.e., in a finished hinged-lid packet) is somewhat longer than the neighboring (second) part of the blank which, is to constitute the front panel or the lid. Those (terminal) sections of the first part which extend beyond the adjacent end portions of the second part are deformed during conversion of the blank into a hinged-lid packet so that they are wedged between and bear against the adjacent lateral panels of the finished lid, i.e., it is not necessary to glue or to otherwise bond or positively secure the reinforcing strip to the front panel of the lid. Reference may be had, for example, to published German patent application No. 32 18 639 A1 which describes and shows hinged-lid packets wherein the reinforcing strip for the front panel of the lid is longer than the front panel and is not bonded to the front panel but is merely wedged or confined between the lateral panels of the lid.
U.S. Pat. No. 4,154,438 (granted May 15, 1979 to Sergnoli for "HIGH SPEED CONVEYOR FOR FEEDING PRESHAPED PIECES OF CARDBOARD") discloses an apparatus for transporting or advancing a series of successive cardboard blanks which are to be converted into hinged-lid packets for arrays of cigarettes in a cigarette packing machine. The blanks which are to be transported in the apparatus of Seragnoli also include parts which are to constitute reinforcing strips for the front panels of the lids of hinged-lid packets; however, such parts are not longer than the front panels, i.e., the reinforcing strips must be bonded to the inner sides of the front panels.
The disclosures of all patents and patent applications which are mentioned in the present specification are incorporated herein by reference.
A drawback of presently known hinged-lid packets wherein the reinforcing strip is longer than the front panel of the lid and the terminal sections of such strip bear against the lateral panels of the lid is that the terminal sections effect a deformation of the lateral panels; this exerts an adverse influence upon the appearance of such hinged-lid packets.